Autonomous smoke and fire detectors should operate with no external supply of energy. Their duration of use is therefore limited by the discharge time of a battery or accumulator. This discharge time is too limited in the known detectors; this imposes maintenance methods and manipulations that are all the more complicated since the detectors are generally located high up, out of a user's direct reach. Indeed, the best location for such a detector is on the ceiling. Manipulating the detector is difficult, especially for persons with reduced mobility. Because the test button is difficult to reach many users never test their detectors, so that these are no longer in operating condition.
Increasing the number or capacity of the batteries/accumulators poses problems concerning production cost and environmental harm.